1. Field of Invention
Exemplary aspects of the present invention relate to a technique for adjusting a potential (referred to as “common potential”) to be applied to an opposing electrode of an electro-optical apparatus.
2. Description of Related Art
In a related art electro-optical apparatus which displays an image using an electro-optical material, such as a liquid crystal, in particular, alternating current drive is adopted in order to prevent the deterioration of the characteristics of the electro-optical material. For example, in an active matrix liquid crystal device using a thin film transistor as a switching element, an almost constant common potential is applied to an opposing electrode opposed to a plurality of pixel electrodes with a liquid crystal sandwiched. At the same time, an image signal indicating the content of an image is periodically inverted using a predetermined potential as a reference, and then is supplied to each pixel electrode. However, if an effective voltage value applied to a liquid crystal is different depending on when the image signal is positive and when the signal is negative, a phenomenon called a flicker (flicking of the display screen), in which the amount of light emitted from the liquid crystal device varies periodically, might occur.
Techniques for preventing a flicker by adjusting a common potential have been disclosed. In these techniques, the common potential is adjusted such that the periodic variation amount of light emitted from the liquid crystal device in the course of displaying the image is minimized (specifically, to minimize a flicker).